用药动作线索诱发海洛因戒断者的镜像神经活动:一项fMRI研究

相关线索能够诱发药物依赖者的心理渴求,而健康人不会对相关线索产生心理渴求。15名海洛因成瘾者和12名没有任何物质滥用的健康被试参与实验,收集了他们在观看相关线索与对照线索时的脑神经活动。结果发现,药物线索能够诱发戒断者更多脑区的活动,包括扣带回和楔前叶。两组被试在对照动作线索刺激诱发作用下,其颞叶、顶叶均出现了较为一致的活动。在用药动作线索诱发作用下,戒断组双侧颞中回、双侧顶下小叶、左侧顶上小叶和右侧额下回显示出显著活动,并且与对照动作线索激活脑区一致;健康组被试除枕叶-颞叶联合区外,没有出现显著的脑区活动。以上结果表明,用药动作线索诱发了海洛因戒断者颞中回、顶下小叶、额下回等镜像神经系统的活动,这些脑区对不同类型的相关线索十分敏感,它们可能通过对用药动作的心理模拟,参与了用药动作线索的快速自动化加工。     

疼痛表情对秒下及秒上时距知觉的影响

采用二分法和泛化法范式,在秒下及秒上呈现时距探究疼痛表情对时距知觉的影响。结果发现,使用二分法,疼痛表情在秒上秒下都显著延长了个体的主观时距,但使用泛化法,疼痛表情仅在秒上产生影响。根据时间分段综合模型和范式特点,该实验结果反映疼痛表情对时距知觉的影响在秒上秒下的作用机制可能不同,在秒下主要是通过唤醒影响,在秒上则可能由唤醒和注意共同调节。     

寻找自我:基于认知神经的观点

默认网络相关研究表明,生物进化的社会适应性建构了自我的认知神经基础,与James的自我结构相对应:主我位于后部扣带回,精神自我位于内侧前额叶,身体自我位于顶下小叶和脑岛; 并且与内侧前额叶、顶下小叶和后部扣带回之间的信息传递相关。个体在基线水平的大脑活动表明,自我是通过后部扣带回接收并调节全脑(包括表征客我的脑区)信息流,随时准备将外界满足需要有利于个体生存的资源纳入其中的神经系统。对于探讨“认识自我”这个古老的哲学问题与现代认知神经科学之间的关系有重要意义。     

Neural correlates of viewing paintings: Evidence from a quantitative meta-analysis of functional magnetic resonance imaging data

Many studies involving functional magnetic resonance imaging (fMRI) have exposed participants to paintings under varying task demands. To isolate neural systems that are activated reliably across fMRI studies in response to viewing paintings regardless of variation in task demands, a quantitative meta-analysis of fifteen experiments using the activation likelihood estimation (ALE) method was conducted. As predicted, viewing paintings was correlated with activation in a distributed system including the occipital lobes, temporal lobe structures in the ventral stream involved in object (fusiform gyrus) and scene (parahippocampal gyrus) perception, and the anterior insula—a key structure in experience of emotion. In addition, we also observed activation in the posterior cingulate cortex bilaterally—part of the brain’s default network. These results suggest that viewing paintings engages not only systems involved in visual representation and object recognition, but also structures underlying emotions and internalized cognitions.     

Independent effects of emotion and attention on sensory and affective pain perception

The present study investigated whether attention and emotion independently influence sensory and affective pain ratings. Fifty-four (27 female) participants rated sensory and affective pain in response to painful mechanic pressure stimulation while exposed to positive, neutral and negative slides from the International Affective Picture System. In doing so, participants were assigned to one of three groups, which focused attention either on the pictures or on the sensory or on the affective aspects of the pressure stimulation. Consistent with the motivational priming hypothesis, sensory and affective pain ratings were generally lower during exposure to positive compared to negative and neutral slides. In line with our assumptions, attention modulated sensory pain ratings with lowest ratings in the picture focusing group and highest in the affective pain focusing group. No attention effect for affective pain ratings and no interactions between emotional and attentional effects on pain perception were found.     

I don’t feel your pain (as much): The desensitizing effect of mind wandering on the perception of others’ discomfort

Mind wandering reduces both the sensory and cognitive processing of affectively neutral stimuli, but whether it also modulates the processing of affectively salient stimuli remains unclear. In particular, we examined whether mind wandering attenuates one’s sensitivity to observing mild pain in others. In the first experiment, we recorded event-related potentials (ERPs) as participants viewed images of hands in either painful or neutral situations, while being prompted at random intervals to report whether their thoughts were on task or mind wandering. We found that the brain’s later response to painful images was significantly reduced immediately preceding “mind-wandering” versus “on-task” reports, as measured via amplitude decreases in a frontal–central positivity beginning approximately 300 ms poststimulus. In a second, control experiment using behavioral measures, we wanted to confirm whether the subjective sense of pain observed in others does in fact decrease during mind wandering. Accordingly, we asked participants to rate how painful the hand images looked on a 5-point Likert scale, again while taking reports of their mind-wandering states at unpredictable intervals. Consistent with our ERP data, we found that the ratings for painful images were significantly reduced immediately preceding mind-wandering reports. Additional control analyses suggested that the effect could not simply be ascribed to general habituation in the affective response to painful images over time. Collectively, our findings demonstrate that mind wandering can directly modulate the cortical processing of affectively salient stimulus inputs, serving in this case to reduce sensitivity to the physical discomfort of others.     

Enhanced occipital and anterior cingulate activation in men but not in women during exposure to angry and fearful male faces

Blood-oxygenation-level-dependent signal was measured with functional magnetic resonance imaging in 24 healthy young subjects (12 men and 12 women) during viewing of angry, fearful, and neutral male and female face pictures. Exposure to angry male as opposed to angry female faces activated the visual cortex and the anterior cingulate gyrus significantly more in men than in women. A similar sex-differential brain activation pattern was present during exposure to fearful but not neutral faces. Previous behavioral studies indicate enhanced physiological arousal in men but not in women during exposure to angry male as opposed to female faces, and brain imaging studies have shown that the occipital cortex and the anterior cingulate gyrus are influenced by activity in the autonomic nervous system as well as by visual attention. Hence, we suggest that the elevated occipital and anterior cingulate activation in men during confrontation with other angry and fearful males may reflect enhanced vigilance in a potentially dangerous situation.     

Experimental manipulation of infant temperament affects amygdala functional connectivity

In this functional magnetic resonance imaging (fMRI) study we examined neural processing of infant faces associated with a happy or a sad temperament in nulliparous women. We experimentally manipulated adult perception of infant temperament in a probabilistic learning task. In this task, participants learned about an infant's temperament through repeated pairing of the infant face with positive or negative facial expressions and vocalizations. At the end of the task, participants were able to differentiate between “mostly sad” infants who cried often and “mostly happy” infants who laughed often. Afterwards, brain responses to neutral faces of infants with a happy or a sad temperament were measured with fMRI and compared to brain responses to neutral infants with no temperament association. Our findings show that a brief experimental manipulation of temperament can change brain responses to infant signals. We found increased amygdala connectivity with frontal regions and the visual cortex, including the occipital fusiform gyrus, during the perception of infants with a happy temperament. In addition, amygdala connectivity was positively related to the post-manipulation ratings of infant temperament, indicating that amygdala connectivity is involved in the encoding of the rewarding value of an infant with a happy temperament.     

疼痛恐惧的形成及其对疼痛知觉的影响

脑岛、杏仁核是疼痛恐惧形成的重要神经网络中心。疼痛恐惧增强了慢性疼痛患者的疼痛知觉体验, 进而加剧抑郁、焦虑情绪和功能损伤程度。脑岛、杏仁核、前额皮层和前扣带回是疼痛恐惧影响疼痛知觉的重要神经基础。通过认知方法干预疼痛恐惧可以改善患者的抑郁、焦虑情绪, 减少功能损伤。未来研究应拓展疼痛恐惧的测量工具, 采用功能磁共振成像技术进一步揭示疼痛恐惧影响慢性疼痛患者疼痛知觉的神经机制。     

Aesthetic value of paintings affects pain thresholds

Pain is modulated by cognitive factors, including attention and emotions. In this study we evaluated the distractive effect of aesthetic appreciation on subjectively rated pain (visual analogue scale;VAS) and multi-channel evoked potentials induced by CO₂ laser stimulation of the left hand in twelve healthy volunteers. Subjects were stimulated by laser in the absence of other external stimulation (baseline condition) and while looking at different paintings they had previously rated as beautiful, neutral or ugly. The view of paintings previously appreciated as beautiful produced lower pain scores and a clear inhibition of the P2 wave amplitude, localized in the anterior cingulate cortex; the inhibition of P2 wave amplitude was lesser or not significant during the presentation of the ugly or neutral paintings, respectively. Dipole source localization analysis of the LEP peaks showed significant changes during different conditions, with a shift from the posterior to the anterior right cingulated cortex while looking at paintings previously rated as beautiful.Our results provide evidence that pain may be modulated at cortical level by the aesthetic content of the distracting stimuli.     

The brain mechanism that reduces the vividness of negative imagery

The present study attempts to locate brain regions that are related to vividness control, a hypothesized mechanism that reduces the vividness of negative imagery by controlling memory retrieval and emotion processing. The results showed that BOLD response in the left posterior cingulate gyrus in the negative imagery condition, in which activation of vividness control mechanisms was considered to be strong, was greater than that in the positive imagery condition, in which the activation of control mechanisms was considered to be weak. Moreover, the activation of this region negatively correlated with the subjective vividness of negative imagery. These results support the idea that the posterior cingulate gyrus may be involved in the suppression of imagery generation. Several previous studies have suggested that the posterior cingulate cortex is involved in both memory and emotion processing. Therefore, the current results indicate that the posterior cingulate gyrus may function as the vividness control mechanism.     

Decreased levels of N-acetylaspartate in dorsolateral prefrontal cortex in a case of intractable severe sympathetically mediated chronic pain (complex regional pain syndrome,type I)

In our previous in vivo proton magnetic resonance spectroscopy ((1)H MRS) study we found reduced levels of N-acetylaspartate in dorsolateral prefrontal cortex of chronic back pain patients. This study tests whether these chemical abnormalities can be detected in other pain states. Using (1)H MRS, we measured levels for N-acetylaspartate and other identifiable chemicals relative to creatine in four bilateral brain regions, including dorsolateral prefrontal cortex, orbitofrontal cortex, cingulate, and thalamus, in a case of intractable severe sympathetically mediated chronic pain [complex regional pain syndrome (CRPS) type I]. The subject's chemical variations in the brain were compared to the same regional chemicals in 10 normal subjects (age- and sex-matched). Univariate statistics showed reduced levels of N-acetylaspartate in bilateral dorsolateral prefrontal cortex and increased levels of myo-inositol in left orbitofrontal cortex of the patient with intractable severe CRPS type I. These data support our original hypothesis that depletion of N-acetylaspartate in dorsolateral prefrontal cortex is a chemical marker of chronic pain, indicating for neuronal degeneration. Unpredicted changes of orbitofrontal myo-inositol may be related to the specific mood/affective state in an extreme pain perception. This is the first report, which identifies chemical markers in the prefrontal cortex for objective measurement and monitoring of CRPS type I. This information might lead to valuable insights into diagnosis and future effective interventions of CRPS type I (e.g., prefrontal brain stimulation).     

负面身体自我女性对身体信息的记忆偏向： 来自ERP研究的证据

采用事件相关电位（ERPs）技术探讨了负面身体自我女性（大学生）对胖-瘦两类身体图片进行再认时的脑内时程动态变化。结果发现,相对于控制组（正常女大学生）,胖负面身体自我女大学生在750~800ms的时间窗口内,“胖图”比“瘦图”诱发出一个更正的ERP波形,差异波的地形图显示该正成分在中前部有更强的激活。进一步对差异波作偶极子溯源分析,结果发现,该正成分主要起源于右侧枕叶附近。这似乎表明,右侧枕叶的激活与身体自我信息的出现有关,与负面身体自我图式的体验有关     

Orienting to guilty knowledge

The Guilty Knowledge Test (GKT; Lykken, 1959) assesses whether suspects conceal information about a crime ( “guilty knowledge”). Previous studies have demonstrated larger physiological reactions to guilty knowledge compared to unknown information. In three experiments, we investigated whether guilty knowledge also demands attention. During an alleged polygraph examination, participants were presented with to‐be‐detected pictures ( “guilty knowledge”), nonsignificant, familiar pictures ( “mere knowledge”), and previously unseen pictures ( “neutral information”) for 250 ms in a modified dot probe task. In all three experiments, probe responses were slower on guilty knowledge trials as compared to the neutral trials. Results are discussed in terms of an information‐processing view on orienting to guilty knowledge.     

Neural substrates for processing task-irrelevant sad images in adolescents

Neural systems related to cognitive and emotional processing were examined in adolescents using event-related functional magnetic resonance imaging (fMRI). Ten healthy adolescents performed an emotional oddball task. Subjects detected infrequent circles (targets) within a continual stream of phase-scrambled images (standards). Sad and neutral images were intermittently presented as task-irrelevant distracters (novels). As previously shown for adults, when the adolescents responded to the task-relevant targets, activation increased in the dorsal attention-executive system including the anterior middle frontal gyrus (aMFG), dorsal anterior cingulate (ACG), posterior cingulate (PCG), insula, and supramarginal gyrus (SMG). Unlike adults, however, the adolescents exhibited strong activation to the emotional distracter images not only in the ventromedial prefrontal cortex (VmPFC), but also in the posterior middle frontal gyrus (pMFG) and in the parietal cortex. Those subjects who had stronger VmPFC activation to emotional distraction also had reduced activation in the aMFG during target detection, suggesting that emotional information may interfere with executive processing in these adolescents. In contrast, pMFG and PCG activation to emotional distracters was positively correlated with aMFG activation to targets, indicating a different role of these regions from the VmPFC. The pattern of activation to task-irrelevant emotional distraction suggests a possible immaturity of brain function in cognitive control over emotional distraction in adolescents.     

Amygdala functional connectivity is reduced after the cold pressor task

The amygdala forms a crucial link between central pain and stress systems. Previous research indicates that psychological stress affects amygdala activity, but it is less clear how painful stressors influence subsequent amygdala functional connectivity. In the present study, we used pulsed arterial spin labeling (PASL) to investigate differences in healthy male adults’ resting-state amygdala functional connectivity following a cold pressor versus a control task, with the stressor and control conditions being conducted on different days. During the period of peak cortisol response to acute stress (approximately 15–30 min after stressor onset), participants were asked to rest for 6 min with their eyes closed during a PASL scanning sequence. The cold pressor task led to reduced resting-state functional connectivity between the amygdalae and orbitofrontal cortex (OFC) and ventromedial prefrontal cortex, and this occurred irrespective of cortisol release. The stressor also induced greater inverse connectivity between the left amygdala and dorsal anterior cingulate cortex (ACC), a brain region implicated in the down-regulation of amygdala responsivity. Furthermore, the degree of poststressor left amygdala decoupling with the lateral OFC varied according to self-reported pain intensity during the cold pressor task. These findings indicate that the cold pressor task alters amygdala interactions with prefrontal and ACC regions 15–30 min after the stressor, and that these altered functional connectivity patterns are related to pain perception rather than cortisol feedback.     

Seeing the future: Natural image sequences produce “anticipatory” neuronal activity and bias perceptual report

This paper relates human perception to the functioning of cells in the temporal cortex that are engaged in high-level pattern processing. We review historical developments concerning (a) the functional organization of cells processing faces and (b) the selectivity for faces in cell responses. We then focus on (c) the comparison of perception and cell responses to images of faces presented in sequences of unrelated images. Specifically the paper concerns the cell function and perception in circumstances where meaningful patterns occur momentarily in the context of a naturally or unnaturally changing visual environment. Experience of visual sequences allows anticipation, yet one sensory stimulus also “masks” perception and neural processing of subsequent stimuli. To understand this paradox we compared cell responses in monkey temporal cortex to body images presented individually, in pairs and in action sequences. Responses to one image suppressed responses to similar images for ～500 ms. This suppression led to responses peaking 100 ms earlier to image sequences than to isolated images (e.g., during head rotation, face-selective activity peaks before the face confronts the observer). Thus forward masking has unrecognized benefits for perception because it can transform neuronal activity to make it predictive during natural change.     

错误相关负波的神经起源及其影响因素

与个体做出错误反应相伴的错误相关ERP成分叫错误相关负波 (error-related negativity, ERN),当前冲突监控理论、表征失匹配理论和强化学习理论从不同的角度对ERN的神经机制进行解释,各理论间并非完全相互排斥。目前大部分研究认为ERN定位于扣带回,部分研究则出现其它脑区的激活,然而,扣带回与其它脑区存在复杂的神经功能联系,ERN 电位很可能是多个脑区电活动在头颅的综合表现,而非某一脑区的单独表现。ERN的神经机制受到实验任务、被试年龄及其意识水平等因素的影响。未来要推动实验室研究走向临床应用,发现与诊断脑电波异常的病人和毒品易复吸人群。     

Mortality Salience Decreases Social Exploration When People Experience Metacognitive Ease Generating Examples of Cultural Value Adherence

In the present research, we integrated terror management theory with work on metacognitive fluency to examine how mortality concerns affect social exploration motives. We hypothesized that mortality salience would decrease desire to explore novel social interactions only when the feeling of being valued by culturally relevant others was secure. Participants (N = 328) reflected on death or physical pain, then generated 3 (metacognitive-ease) or 12 (metacognitive-difficulty) examples of past behaviors that their peers valued (vs. neutral behaviors). Metacognitive fluency was expected to enhance feelings that existing social bonds were secure. Finally, we assessed participants’ desire to explore novel social interactions. Death thoughts decreased participants’ desire to explore novel social interactions when they experienced “ease” generating examples of culturally valued behavior.     

Using Potential Performance Theory to Test Five Hypotheses About Meta-Attribution

The aim of this study was to compare the reaction times and errors of Spanish children with developmental dyslexia to the reaction times and errors of readers without dyslexia on a masked lexical decision task with identity or repetition priming. A priming paradigm was used to study the role of the lexical deficit in dyslexic children, manipulating the frequency and length of the words, with a short Stimulus Onset Asynchrony (SOA = 150 ms) and degraded stimuli. The sample consisted of 80 participants from 9 to 14 years old, divided equally into a group with a developmental dyslexia diagnosis and a control group without dyslexia. Results show that identity priming is higher in control children (133 ms) than in dyslexic children (55 ms). Thus, the “frequency” and “word length” variables are not the source or origin of this reduction in identity priming reaction times in children with developmental dyslexia compared to control children.